I was in the indian grocer this afternoon, and a bunch of people were
lined up waiting for "tawa".  What is "tawa"?

Hi! Thanks for the question.

The "tawa" is not an Indian food but an Indian kitchen utensil.

"A tawa is a round, thick iron griddle, it is also slightly concave in
the center. It is used when very high temperatures are needed and is
mostly used for Indian unleavened breads called chappati or rotis. It
is also used for cooking some unique dishes which require fast cooking
with the outer rim is used to keep the dish warm. Popular in street
food especially Pau-Bhaji is a typical tawa dish and needs to be
constantly stirred to avoid burning, and is served straight out of the
tawa and eaten immediately on sour dough bread."

"A description of all the Indian coooking techniques. Find out how to
cook great Indian food"
http://www.indianfoodsco.com/Classes/techniques.htm

What you probably heard was of bread cooked in a tawa called "TAWA
PARATHA". It is also being sold in Jaipore Royal Indian Cuisine a
restaurant in New York.

Jaipore Royal Indian Cuisine - Indian Restaurant in Brewster, NY
http://www.culinarymenus.com/jaipore.htm

Another tawa food could be found here:
http://www.cookinginindia.com/tawa.html

In a nutshell the tawa is just practically a tool used in cooking.

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tawa Indian food dish
 
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Regards, 
Easterangel-ga 
Google Answers Researcher

Appreciate the fast response!